<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>p7_相对定位</title>
    <style>
        .fu{
            background-color:darkgreen ;
        }
        .fu>div{
            width: 100px;
            height: 100px;
        }
        .z1{
            background-color:  #f00;
            position: static;
        }
        .z2{
            background-color:#0f0;
            /* 相对定位；参照物为自己原来的位置，不会脱离文档流（释放布局空间）*/
            position: relative;
        }
        .z3{
            background-color: #00f;
        }
    </style>
</head>
<body>
      <div class="fu">
          <div class="z1"></div>
          <div class="z2"></div>
          <div class="z3"></div>
      </div>
</body>
</html>